Acidic extracellular microenvironment promotes the invasion and cathepsin B secretion of PC-3 cells.

BACKGROUND This study aimed to investigate the effect of acidic microenvironment on the invasion of prostatic carcinoma PC-3 cells and to explore the potential mechanism. MATERIAL AND METHODS PC-3 cells were maintained in medium at different pHs (pH 7.4, pH 7.0 and pH 6.6). Invasion and metastasis of PC-3 cells were investigated in vitro. Acridine orange staining was performed, followed by laser confocal scanning microscopy for the localization of lysosomes. Western blot assay and ELISA were employed to evaluate the effect of acidic microenvironment on the cathepsin B secretion. RESULTS Acidic microenvironment remarkably promote the invasion and migration of PC-3 cells (P<0.01). Moreover, at acidic extracellular pH (pHe), an obvious shift of lysosomes from the perinuclear region to the periphery was observed. Western blot assay and ELISA revealed that acidic microenvironment promoted the cathepsin B secretion in PC- cells. CONCLUSION Acidic microenvironment may significantly promote the invasion of PC-3 cells and increase the secretion of cathepsin B. This suggests that the acidic microenvironment induced invasion of PC- cells is related to the elevated cathepsin B secretion.